AKO AKO-16520, User Manual

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18
1652H302 Ed.03
Alarms
The device warns the user through an on-screen message, activation of a relay (only devices with 5 relays and if
o10 =1) and a sound alarm when the criteria programmed in the parameters are met.
Maximum / minimum temperature alarm
It shows the message “ AK ” or “ AL ” when the temperature in probe 1
reaches the value configured in parameters A1 (maximum temperature)
and A2 (minimum temperature).
This value may be:
Ÿ
Absolute ( A0 =1): The temperature at which the alarm should activate must be indicated in A1/A2 .
Ÿ
Relative to the SP ( A0 =0): The increase or decrease in the number of degrees necessary for the alarm to
activate, in relation to the set point, must be indicated in A1/A2 . This option enables us to change the set
point without having to reset the maximum and minimum alarms.
Parameter A10 establishes the differential of both parameters (Hysteresis).
Example
We configure the following parameters in a controller:
SP =2, A1 =10, A10 =2
-If A0 =0 (Relative to the SP), the maximum temperature alarm will activate when 12 degrees are
reached in probe 1, and will deactivate when 10 degrees are reached.
-If A0 =1 (Absolute), the maximum temperature alarm will activate when 10 degrees are reached in
probe 1, and will deactivate when 8 degrees are reached.
External alarm / severe external alarm
The message EA (External alarm) or SEA (Severe external alarm) is
displayed when the digital input configured as external alarm or severe
external alarm is activated.
The severe external alarm also deactivates all the loads and, therefore, temperature regulation stops. When this
alarm disappears, the device returns to its normal operation.
Al At least one of the digital inputs must be configured as an external alarm (
I10 or I20 =2) or as a severe external
alarm ( I10 or I20 =3).
Probe error alarm
If one of the enabled probes is crossed, in open circuit or out of range, the message
E1 , E2 or E3 will be shown, depending on whether probe S1, S2 or S3 is involved.
Evaporator probe error alarm due to moisture ingress
If, at the start of defrost, the temperature in probe S2 is 20°C higher than the temperature in
probe S1, the defrost ignores probe S2 and completes due to time-out.
The display shows the message
E2 , activates the alarm relay (only devices with 5 relays and if
o10 =1) and sound alarm.
The alarm can be silenced, but the
B
alarm icon will not disappear until:
Ÿ
The controller is switched off and then on again.
Ÿ
Defrost without error is started in probe S2.
If the 2nd evaporator probe ( l20 =8) has been enabled, it will behave in the same way, but displaying the message E3 .